Angela Merkel has been a pillar of stability for Germany and the western world for the better part of two decades, but the party that kept her in charge of Europe’s biggest economy is grappling with the power vacuum she’s leaving behind.

A botched succession plan two years ago has put the Christian Democratic Union in a bind. Instead of a smooth transfer of power, the traditional anchor of German politics faces a messy free-for-all to defend its hold on the chancellery.

A two-day convention that starts Friday to elect a new leader can go two ways: kick-start a process of renewal or usher in a period of stagnation and decline. While the party leader usually goes on to be candidate for chancellor for Germany’s conservative bloc, that step isn’t automatic this time.